ISLAMABAD: Pakistan barred the head of Bhoja Air whose jet crashed near Islamabad from leaving the country Saturday as it began a probe into the disaster that sparked anger among distraught relatives.

The flight from Karachi came down in fields near a village on the outskirts of the capital on Friday evening, killing all 127 people onboard.

Interior minister Rehman Malik said a committee had been set up to investigate the crash and the head of the airline Farooq Bhoja had been put on an "exit control list", meaning he is banned from leaving Pakistan.

The airline insists the crash was caused by bad weather as the plane tried to land at Islamabad's international airport during a thunderstorm and not a technical problem as was widely speculated.

Civil Aviation Authority (CAA) officials said the second-hand Boeing 737-200 was nearly 30 years old, but an airline spokeswoman said the plane's age had no bearing on the tragedy.

"The aircraft was old and second hand but it is not something unusual. The fleet of state-run Pakistan International Airlines (PIA) also runs old aircraft," Bhoja Air official Masham Zafar told AFP.

"There was no technical issue and bad weather is to be blamed."

She said the plane left Karachi with CAA approval and was given clearance to land at Islamabad.

Prime Minister Yousuf Raza Gilani told reporters a judicial commission would investigate the crash while information minister Qamar Zaman Kaira said the findings of an initial investigation could be released as early as Saturday evening.

Distraught relatives wept as they collected shattered remains of loved ones from Islamabad's main hospital, the Pakistan Institute of Medical Sciences (PIMS), and their tears turned to anger at what they saw as official fecklessness.

A woman identifying herself as Mrs. Hassan said she had come to collect the body of her cousin Mohammad Yunus.

"It's sheer incompetence of the government. This is the second major accident here in less than two years but the president and the prime minister remain unmoved," she said.

"If the weather was bad why they did not warn the pilot. Why did they allow the plane to land?"

Abdul Raoof blamed the airport control tower for negligence over the crash, which killed his cousin.

"If the weather was bad the plane should have been turned away," he said.

"It is also a mistake of the airline. They sacrificed 127 lives just to save some fuel."

All 127 people on board -- 121 passengers and six crew -- were killed when the plane crashed and burst into flames at around 6:40 pm on Friday. There were 11 children among the dead.

Boeing offered "profound condolences" to the victims' families and said it would provide technical assistance to the investigation into the Bhoja crash.

Military and aviation officials said bad weather was probably behind the crash, as there was a hail and thunderstorm over the city at the time.

A senior PIA engineer told AFP the age of the aircraft mattered less than its flying hours, and said he thought an air pocket -- a patch of low air pressure -- could be to blame.

"Since it was approaching the airport to land it was obviously flying low -- between 3,000 and 4,000 feet above the ground," he said.

"Visibility was also low because it was raining and there was thunder and lightening. The pilot lost control and apparently failed to lift it out of the air pocket."